Thanks to the recent advent of digital TV transmissions technology, TV broadcasters are now capable of providing much more than the traditional, analog broadcast TV.
The transmission of digital TV signals may occur in different ways. For example, in Digital Terrestrial Television (DTT) networks, the broadcast signal is broadcast “over the air”, and is received by an antenna similar to that used for receiving analog TV signals. Other means for broadcasting digital TV make use of satellites or cables.
Digital TV can be enjoyed using traditional TV sets exploiting a so-called “Set-Top Box” (STB), which is an electronic equipment basically adapted to decode signals, particularly digital signals, received, e.g., through the TV antenna, and to provide the decoded signals to the TV set for displaying the multimedia content on the TV monitor.
Advanced STBs can be more than just signal decoders, and may be programmed to execute applications. Essentially, the STB comprises a programmable data processing apparatus (a computer) adapted to run software, which decodes the digital TV signal and also executes the application software.
In particular, such applications that may be executed by the STB may allow an interaction of the user, e.g. through the STB or, possibly, the TV set remote control device, with service providers in an IP network (typically the Internet), over an available communications network, forming the so-called “return channel”; which is the physical path used by the STB to enable the client interact with the server of the service provider; for example, the return channel may consist in a dial-up connection over the Public Switched Telephone Network (PSTN) to an access provider providing access to the IP network, using an internal or external modem, or an xDSL line, or a wireless connection, e.g., a connection to a GPRS or packet-switched) UMTS network.
Interactive TV (iTV) can he exploited by users to send information (e.g., votes, questionnaires, requests for a service) back to a service center in the IP network, through the STB's return channel.
Examples of iTV involving a cooperation of a broadcast iTV network with other communications networks are known in the art.
For example, EP-A-1467576 describes a method for selecting and tuning a broadcast processing system (a combination of an STB and a TV set) to a broadcast channel. The viewer uses a mobile terminal for connecting to a mobile service, for example with the WAP or a Web browser, or utilizing SMS messages. The mobile terminal downloads a mobile application, such as a calendar event that alerts the viewer when a selected TV program is about to start.
The STB, having a Bluetooth® communication module or other wireless interface, is instructed by the mobile terminal and tunes onto the selected program.
In WO 03/56830, a user contacts a server arrangement via the mobile terminal, and receives a request for an ID number of the STB he/she is present at. The user sends the ID of the STB to the server arrangement, which responds sending a control code to the STB, which is shown to the user and which the user sends back to the server arrangement via the mobile terminal, to show that he/she is actually present at that particular STB. The connection is thus established, and the user is inquired for the desired service.
WO 03/94123 describes an iTV payment system used for the purchase of goods, services or entry into a game or competition. The user sends a code derived from a requested service and a unique user apparatus identifier number, via a mobile phone and by messaging to a designated number; once the message is received by the messaging center, the message is transmitted to a broadcaster/service provider which then interprets it, identifying which user's apparatus is requesting the services, and which service is being requested. The user pays with the mobile phone, and the receipt of the message is the confirmation to the broadcaster/service provider that a charge has been billed to the user's mobile phone: the broadcaster/service provider can then instruct its broadcasting/transmitting equipment to provide access to the desired service.